name: improve-audio-quality
description: FFmpeg noise reduction for video and audio. PROACTIVELY activate for: (1) video denoising (nlmeans, hqdn3d, atadenoise), (2) GPU denoising (nlmeans_opencl, nlmeans_vulkan), (3) audio noise reduction (afftdn, anlmdn), (4) film grain removal, (5) low-light cleanup, (6) compression artifact cleanup. Provide concise commands, stronger-by-default settings, and quick tuning guidance.
Defaults (Stronger, Still Safe)
Video (quality)
-vf "nlmeans=s=4:p=7:r=15"
Video (fast)
-vf "hqdn3d=5:4:8:6"
Video (temporal)
-vf "atadenoise=s=9:p=7"
Video (GPU)
-vf "hwupload,nlmeans_opencl=s=4:p=7:r=15,hwdownload,format=yuv420p"
Audio (general)
-af "afftdn=nf=-28:nr=14"
Audio (speech)
-af "anlmdn=s=0.0002:p=0.01"
Quick Use
Stronger video cleanup
ffmpeg -i noisy.mp4 -vf "nlmeans=s=4:p=7:r=15" -c:v libx264 -crf 18 output.mp4
Fast video cleanup
ffmpeg -i noisy.mp4 -vf "hqdn3d=5:4:8:6" -c:v libx264 -crf 18 output.mp4
GPU video cleanup
ffmpeg -i noisy.mp4 -vf "hwupload,nlmeans_opencl=s=4:p=7:r=15,hwdownload,format=yuv420p" -c:v libx264 -crf 18 output.mp4
Audio cleanup
ffmpeg -i noisy_audio.mp4 -af "afftdn=nf=-28:nr=14" -c:a aac -b:a 192k output.mp4
Tuning (Minimal)
nlmeans: raise s for more reduction (3-6 typical); reduce p to preserve detail.hqdn3d: increase first two values for stronger spatial denoise; last two for temporal.afftdn: lower nf (more negative) to be more aggressive; raise nr for stronger reduction.
When to Apply
- Noisy low-light footage
- Grainy film scans
- Compressed/streamed artifacts
- Room tone or steady hiss
